Magecraft

Magecraft (魔術, Majutsu?), or Thaumaturgy, is the artificial reenactment of Mystery, which is ordinarily possible only by inhuman beings.[1][2]

It is the ability to bring about what is possible through science with supernatural means; although the process is considered a miracle, the result is not. The limits of Magecraft have changed with time, as science evolved and Magic from the past became possible through science.

There exists no impossibility for modern Magecraft within the rules of the world and limits of human intellect; there are limitations, however, where it only appears that something is possible. Because Magecraft acts as the reenactment of preexisting phenomena, it is impossible to use it to create new Mysteries; even with an infinite amount of research, there exists a "wall" preventing human wisdom from doing so in the current era. The realm past this "wall" is known as Magic.

Modern Magecraft is inferior to that from the Age of Gods in terms of magnitude because magi from that era had acquired their magical energy from the Root directly. The difference between modern and traditional Magecraft is explainable by the difference in civilizations - while the civilization of the Age of Gods existed side-by-side with the truth, the civilization of the Age of Man exists in order to search for the truth.

Contents

Thaumaturgy is the general term used to refer to the several modern schools of Magecraft such as Astrology, Kabbalah, Alchemy, and Shinsendou. Divergences can be found among different schools, but the fundamental basis is “to convert Magical Energy inside the user’s body to transform the external world”. The practitioner acts in accord with the system that each school operates under to execute a pre-built program. That “program” is a set of universal rules that interfere with nature once they are enforced. The power that enforces those rules is the magical energy of the magus and the command to do it is made through his Circuits. The greater the interference, the greater will be the amount of magical energy consumed.

Being originally magic, Thaumaturgy draws upon a predetermined power from the Root. However, because that amount of power is fixed, the more people draw from it at the same time, the more Magecraft’s capacities become mundane. In short, the greater is the collective number of magi, the weaker their individual power. Each school engraves their system of Thaumaturgical Theory into the world and uses the rules of that system to operate their spells. The efficiency of a system depends on how disseminated it is, as in the more people believe or use it. It is not uncommon for a system to not work properly when used outside its place of origin. In that regard, the teachings and holy words of the Church is the Thaumaturgical Theory with the greatest number of believers and effective area. Note that the case is different with magic foundations that are not academia or religions but rather are passed down through personal orally transmitted teachings, the limited inheritance in clans, etc. As long as the rules of those foundations are met, it is possible to exhibit the same basic effect no matter where one is in the world.

The main aim of the Magi’s academia is to make the impossible possible. If something cannot be achieved with modern Thaumaturgy, the magi research and develop their arts just for the sake of changing that. Powerful sorceries like High Thaumaturgy and Greater Rituals are ultimately challenges in order to reach the goal called Magic. After a certain point of development, differences between power and even between Magic and Thaumaturgy start to lose their importance in practical terms. Battles between two great Magi will not be decided by their power, but by who possesses the system whose rules has the fewer tears. It is not the power behind them, but the concepts they work under.

The activation of magecraft from an established school requires following a strict set of protocol, one step of which is spellcasting. When compared to the application process of a document, the act of application, acceptance, review, and issuance, spellcasting is the application step of magecraft. It is mostly a convention when utilizing magecraft with a broad foundation, but it has potent self-suggestive powers for those who practice their own style of magecraft. As the Magic Circuits that shape magecraft already exist inside a magus' body, incantations are the "personal adage" that help the magi transform themselves, a method to efficiently activate and mobilize the Magic Circuits.

Although magecraft has died out as of the 2030s in the Fate/Extra world, wizards are able to utilize Code Casts both in the virtual world and real world. They also possess Magic Crests.[3]

Spellcasting (呪文詠唱, Jumon Eishō?) is not a method used to speak to the World, but to oneself. Different magi will utilize different incantations even for the same spell due to their distinct natures. Spells that speak to the World, classified as Grand Spells or Grand Rituals, and not to the individual are impossible for an individual to use under normal circumstances.[4]

Magecraft is that "which governs the skills of past humans that science cannot explain" and science is that "which gathers the technology of future humanity that sorcery cannot reach." The two disciplines are absolutely incompatible with each other, but they are similar in a single respect. The pursuers of each practice seek continued prosperity, protecting the future of humanity.[5]

Equivalent Exchange (等価交換, Tōka Kōkan?) – The primary rule of Thaumaturgy. In order to create something, another object must be given as a price. It may also involve modification to an existing object. The base of all Thaumaturgy is the use of magical energy to produce something that either already exists or can exist. That which falls into the Phantasm category, something made entirely out of images and might not even exist naturally anymore, will eventually be wiped out by the world for being in conflict with this rule.

Shirou Emiya is able to bypass this rule to some extent when it comes to his Projections, since everything that he Traces is actually being pulled out of his own internal world by the power of his Reality Marble.

It is also standard amongst Magi to make up for every deed, item or piece of information given to them with repayment of equal value.[6]

A Thaumaturgical Foundation (魔術基盤, Majutsu Kiban?) is a Thaumaturgical Theory (魔術理論, Majutsu Riron?) "engraved" upon the World in the form of scholarship or religion ─ a body of pre-established rules, fomented per the faith of the populace. It is also called a Greater Magic Formula (大魔術式, Dai Majutsu Shiki?) as a cluster of Magic Formulae (魔術式, Majutsu Shiki?), each of which runs a Magecraft(program) written within it when a Mage sends a command through their Magic Circuits to it.[7] In other words, Foundations are necessary for the usage of Magecraft.

If it is believed that the subject of a Mystery "exists," the World permits its existence. Definite affirmation of said belief is not required. For example, even though the majority of modern humans reject the existence of ghosts, modern science cannot outright demonstrate that they do not exist, and, thus, within the unconscious, there lurks the vague suspicion that "they might indeed exist." This sort of "suspicion" falls under the category of "faith." "Ignorance" is the force that opposes "faith." If the existence of ghosts is itself utterly unknown, faith cannot foment.

Each Thaumaturgical School has its own Foundation and the further a user is away from their Foundation, the weaker the effect of their Magecraft becomes.[8] For instance, Icecolle clan lost their power as they moved from western Europe to Siberia to escape witch-hunting. In any case, if faith in a mystery is widely disseminated, a relevant Thaumaturgical Theory gains robustness. For a Theory weak in faith, "the power that engraves" is similarly infirm, and in other nations where its mystery is wholly unknown, implementation of descendant magecraft fails. The Thaumaturgical Theory of the Church, in the form of its Holy Sacraments, is the most widespread and well-stabilized in the world. The only exception are those magic foundations that are passed down through personal orally transmitted teachings, the limited inheritance in clans, etc. As long as the rules of their foundations are met, it is possible to exhibit the same basic effect, no matter where one is in the world.

The Taiji (太極, Taikyoku?) is a philosophy originated in ancient China, a graphical representation of the Yin-Yang theory. Those who practice Western magecraft are incompatible with Chinese philosophies.[11]

Alchemy – A school that focuses its studies around the flow of matter, most alchemists research on conversion of matter, but those of Atlas delve in the conversion of phenomena.

Kabbalah (カバラ, Kabara?), the Hebrew word for '"tradition", is a major Thaumaturgical School from Europe who's name was coined by Solomon ibn Gabirol. Solomon List of createdgolems as his specialty. Aoko Aozaki uses one of its ancient branches, the Notarikon. Other branches include the Temurah and Gematria, the latter which was the basis for the Numerology of Michael Roa Valdamjong.

Resistance (抗魔力, Kōmaryoku?), a power inherent to anyone with Magic Circuits, the capacity to resist spells which aim to control the target by the spiritual medium (those along the lines of sleep, paralysis and coercion). By circulating magical energy inside his Circuits, one can reject outside magical energy that tries to invade his/her self. Therefore, it is possible to disrupt a spell before it can complete itself. A very efficient form of defense, it makes it difficult to affect even lesser magi. Also, those who are not Magi but still possess Magic Circuits may unconsciously protect themselves like this. Because of it, most magi use spells capable of physical interference rather than just spiritual ones.

However, what is being rejected is the magical energy, the spell itself is not nullified. A spell that has already been completed and is manifesting its effects cannot be cancelled like this. Caster, however, is an exception. She can disrupt even completed spells due to her absurd amount of magical energy and because the structure of modern Magecraft’s spells are far inferior to those of her time.

Breathing and Walking (呼吸・歩法, Kokyū Hohō?) is a key concept in Magecraft and Martial Arts. Though mainly affecting one’s physical fitness, it also plays a role in the strength of nature interference. The absorption of outer energy (breath of life) to connect your inner world to the outer world. The acts of inspiring, expiring and everything in between are part of a process that allows one to take in or release the gods. The Magi use incantation spells to cause a specific phenomenon to occur, but those whose breathing, movement, body and very existence can cause nature interference are beyond that. An example would be the Shinto practice of banishing evil spirits and other unnatural forces just by clapping. However, this particular skill is something that takes a lifetime to learn.

Not valued by Western magi, but among the teachings of the east, the techniques of breathing and walking are high-level secrets that can’t just be imitated or easily learned. Therefore, Eastern schools always search for at least one individual capable of mastering them in a generation.

Sometimes however, there are those who are simply born with the “proper way of breathing and walking”. As a result, their own body acts as one pure, natural Circuit. Those humans can reproduce greater mysteries than the magi without knowing anything about Thaumaturgy. When found while still in their childhood, they are treated as holy children or prodigies and usually taken in by those who follow the supernatural path. Still, there are cases of those who grow up without learning about their true nature.

Souichirou Kuzuki's martial arts training gave him some proficiency in this skill, although it is nothing near the level of Magecraft. Shirou Emiya's daily Magecraft training involves breathing exercises and during the fight with Gilgamesh he tried to bring his breathing pace down to normal conditions.

A magus normally has the capacity to manipulate at least one of them. However, there are cases of those who can manipulate Elements that are completely different from any of the ones specified above. Within the Mage’s Association, individuals like these tend to be from either very selective houses or not be part of the Association at all. Cases of magus who possesses more than one Elemental Affinity, and even the affinity to Compound Elements, are also known. Usually said individuals try to master spells that make use of more than one Element at the same time (ex: “liquid manipulation” through the use of Water and Wind Elements). Those capable of manipulating all five Elements receive the title of Average One and are highly valued by the Mage’s Association. Methods to change one’s Elemental Affinity exist, but they are very painful and dangerous.

The set of Elements that, according to the teachings of Magecraft schools, are the basic substances that shape the world: Fire, Water, Earth, Wind and Void (Ether) or Water, Fire, Earth, Wood and Metal. Fire is called normal and Wind is said to be noble.

Origin (起源, Kigen?) is the starting point that defines one's existence and directs one's actions throughout life. It is the driving force that comes from within the Root that has managed to stream out of the Source and take on material form. The form it can take on at times is that of a human being, and all humans match their actions to be in harmony with the driving force that originated them from the moment they enter into the world. These actions are more along the lines of an inherent compulsion that could be called a person's instinct rather than a conscious decision. If a person becomes awakened to their Origin, it becomes nearly impossible to stray from their Origin if it's even possible in the first place. It becomes an impulsive behavior one would follow as though it were an absolute order. The Ryougi Family is able to awaken the Origin of newborns, and Souren Araya is capable of awakening one to their Origin after receiving consent from the person beforehand. Araya claims that death and Origins are related, and his various experiments on death are used to further his knowledge on them.[12]

Under the system of Magecraft, Origins are used to describe precise details about a magus, while Elemental Affinity indicates one’s general alignment.[7] Magi with an Origin that is strongly expressed outwardly are sometimes removed from the normal alignments and there are times that the origin itself becomes the alignment. Most of those magi exhibit their talents as extreme specialists, allowing them to potentially reach higher grounds than normal magi. Even those without an Elemental Affinity are sometimes still capable of casting spells simply by following their Origin. It's possible for them to overcome great obstacles such as a lack of Circuits or a lack of talent for Magecraft altogether. Shirou Emiya's origin is "Sword" and his alignment as a Magus is also "Sword". He is unable to use magic of the five great elements with precision because he doesn't have any of them as an alignment, but it does allow for the manifestation of "Unlimited Blade Works."[13]

Noble Colors System is a special classification system of the Mage's Association used to grade special abilities such as Sorcery Traits. The term "Noble Colors" is used to refer to special and innate things where the workings of the magic circuit are close to the movements of a celestial body (normally they're closer to the movements of the crust), and is innate and special.[13] In practice, however, it relates mostly with Mystic Eyes. Powerful eyes shine Gold, while those with powers that reaches the realm of gods have a multi-colored glow, such as the case of Jewel and Rainbow. Jewel-ranked Eyes are exclusively possessed by Holy Spirits and Magical Beasts from the Age of Gods.

Sorcery Trait (魔術特性, Majutsu Tokusei?) is a Thaumaturgy "special feature", the general term given to special abilities that are somewhat related to Magecraft. To a lineage of magi, their Sorcery Trait is a treasure as valuable as (or even more than) their Magic Crest. Although clan inherent Sorcery Traits are the more common kind, those that are unique and innate to a single individual are not unheard of. Mystic Eyes are considered a Sorcery Trait.

Known Sorcery Traits by characters and clans:

Edelfelt clan: Sisters (aka Ore Scales) – The capacity of effectively having two heirs to succeed their lineage and Magic Crest.

Fraga clan: Gods Holder (aka Tradition Carrier) – A special quality found in the old blood of this family, remains of a mystery of the Age of Gods in the form of a virus. Not an hereditary trait carried in the genes, but rather a pathogen that has been transmitted throughout the generations. Allows the recreation and use of the Noble PhantasmFragarach.

Illyasviel von Einzbern: Wish-Granting – Spellcasting without possessing the knowledge of the spell itself; to skip the thaumaturgical process altogether and recreate miracles just through the use of magical energy. Still bound to the limitations of the Magic Circuits.

Kirei Kotomine: A nameless Sorcery Trait used for opening wounds that makes him fit for spiritual surgery.

Magecraft [Others]
A general term representing activities that artificially re-enact Mysteries/Miracles.
Although there were some differences depending on traditions and schools, the basic principle was still "the transformation of the magical energy that exists within the practitioner or the environment".
The practitioner would issue Commands according to the Foundation (System) of his school, and this would cause the execution of a predetermined Program.
Magical energy was the electrical current required to deliver the command.
Although magecraft gave the impression of omnipotence, it fundamentally produced Mystery through the principle of equivalent exchange.
It was possible to transform one thing into another, but it was impossible to produce something from nothing.
However, the essence of magecraft as a discipline was to challenge that "Nothingness", and endeavor towards the impossible. Large-scale spells such as the so-called Grand Sorceries, Grand Rituals were really purposeless if not for attempting to reach " " (Kara) or True Magic.
Kara no Kyoukai was a story of one magus' attempt at challenging "Nothingness".

Magecraft [Term]
A general term for the act of artificially reenacting mysteries and miracles.
Although each school has its individual differences, it is basically a mechanism for using the magical energy in the practitioner's body or the outside world, in order to reenact a predetermined phenomenon. The practitioner sends an order (command) to the foundation (system) controlled by their school, and a pre-made function (program) is executed. The "electrical current" needed to send that command and execute the program is magical energy.
Though sorcery may seem almighty, it is basically the bringing about of mysteries by means of equivalent exchange. Accordingly, sorceries powerful enough to interfere with Nature will obviously require enough magical energy (mana) to fill Nature just to execute them.
There is a limit to the sorceries that can be executed using an individual's magical energy alone.

Spellcasting [Others]
A necessary step in the activation of magecraft.
While utilizing an established school of magecraft, one must strictly follow a set protocol. Spellcasting is one step in this protocol.
An analogy would be the application process of a document, which would include application, acceptance, review, and finally issuance. Spellcasting would be the "application" step.
In the case of utilizing magecraft with a broad Foundation, spellcasting is mostly a convention. However, for those who practice their own style of magecraft, spellcasting has potent self-suggestive powers.
In the bodies of magi, the Magic Circuits which shape magecraft already exist.
Incantations are the "personal adage" that help the magi transform themselves. They are a method to efficiently activate and mobilize the Magic Circuits.
Spellcasting is not a method to speak to the World, but a method to speak to oneself. Even for the same spell, different magi will utilize different incantations due to their distinct natures.
As an aside, spells that speak to the World rather than oneself are classified as Grand Spells or Grand Rituals, and it is impossible for an individual to use such spells.

Keywords to learn about Thaumaturgy•Alignment
Determines the orientation of the magic that the magus is skilled in

•Attribute
One of the factors determining the effect of one's magic. There are multiple genres like reinforcement and projection.

•Magic foundation
System engraved in the world in advance, which renders magic usable. Takes the form of academia and religion.

•Origin
The orientation at the time that an event occurred.
The origin is what defines the existence as an existence. In magery, it also is used under the meaning of alignment.

•Magic formula
Something included in a magic foundation and in which the function of magic is recorded.
The magus sends a command to the magic formula, puts magic power into it, and thereby activates the function of magic incorporated into the formula in advance.

Land and Thaumaturgy
To use magic, what is necessary is a sequence in which a magus, once establishing contact with a magic foundation engraved in the world, sends a command to the magic foundation and executes a premade function. At this time, the fuel used for executing the function is magic energy, and the magus will have to send the command at the same time as the magic energy.

Magic foundations are magic theories that magus schools have engraved in the world, and magic is started up in accordance with those rules and systems. For example, the magic theory with the largest foundation is the “Teaching of the Lord” of the Church. Magic foundations engraved in the form of academia and religions fuse intimately with the veins of the land, and the magus using that magic foundation can perform magic anywhere in the world. However, if the magus leaves the land where his magic foundation was engraved in, he loses the backup of his land, and the force is certain to deteriorate.

Note that the case is different with magic foundations that are not academia or religions but rather are passed down through personal orally transmitted teachings, the limited inheritance in clans, etc. As long as the rules of those foundations are met, it is possible to exhibit the same basic effect no matter where one is in the world.

Matou Zouken
The Makiri line moved from their homeland to Fuyuki and fell. For a magus to leave their land carries the meaning of departing from their own magic foundation and is extremely risky.

Magecraft [Term]
A general term for the act of artificially reenacting mysteries and miracles.
Although each school has its individual differences, it is basically a mechanism for using the magical energy in the practitioner's body or the outside world, in order to reenact a predetermined phenomenon. The practitioner sends an order (command) to the foundation (system) controlled by their school, and a pre-made function (program) is executed.
The "electrical current" needed to send that command and execute the program is magical energy.
Though sorcery may seem almighty, it is basically the bringing about of mysteries by means of equivalent exchange. Accordingly, sorceries powerful enough to interfere with Nature will obviously require enough magical energy (mana) to fill Nature just to execute them.
There is a limit to the sorceries that can be executed using an individual's magical energy alone.
Also, sorceries that affect other people's minds and change the course of their thoughts require no physical compensation, but the practitioner will inevitably find their own thoughts being pulled in that altered direction as well. As the saying goes, before you embark on a journey of revenge, dig two graves. Because the study of curses is looked down upon as unscholarly by the Association, they have fallen far behind the Middle East in that particular field.

Magecraft [Magecraft]
A general term for the act of artificially reenacting mysteries and miracles.
Although each school has its individual differences, it is basically a mechanism for using the magical energy in the practitioner's body or the outside world, in order to reenact a predetermined phenomenon.
The practitioner sends an order (command) to the foundation (system) controlled by their school, and a pre-made function (program) is executed.
The "electrical current" needed to send that command and execute the program is magical energy.
Though magecraft may seem almighty, it is basically the bringing about of mysteries by means of equivalent exchange.
Even the exceptionally talented Rin, in exchange for her versatile sorcery trait, will find herself afflicted by a chronic lack of money her entire life.
Also, sorceries that affect other people's minds and change the course of their thoughts require no physical compensation, but the practitioner will inevitably find their own thoughts being pulled in that altered direction as well. As the saying goes, before you embark on a journey of revenge, dig two graves.
Because the study of curses is looked down upon as unscholarly by the Association, they have fallen far behind the Middle East in that particular field.

Taiji [Others]
A philosophy originated in ancient China, a graphical representation of the Yin-Yang theory.
It attempts to capture the essence of everything on a conceptual level: those that are active are defined as Yang (white), and the opposite are defined as Yin (black).
The Taiji symbolizes opposing concepts such as day and night, light and darkness, male and female. At the same time, you may also call it a condensed version of the ever-changing, dynamic World.
Furthermore, there is a dot of Yin in Yang, and conversely a dot of Yang in Yin. This indicates that the distinction between Yin and Yang is not absolute. There is darkness even in light.
Taiji is the "one" at the beginning, the Yin and Yang that divide the "one" are called Liangyi (Ryougi).
As an aside, the magi in this story were all practitioners of Western magecraft who were incompatible with Chinese philosophies.

Origin [Others]
The direction of everything that arose from fundamental cause. The α that enabled the existence of α, the absolute order that existed at the very core.
For instance, something with the Origin of "taboo", regardless of being born as a human, animal, or plant, would always exist to go against the morals established by the collective.
It was the idea that, independent of the process of reincarnation, humans acquired bodies and wisdom from the directional force at the point of origin, and acquired personalities that were only slightly different from their prior lives.
Individuals who awakened their Origins would be consumed. This was due to "personality" being something merely on the magnitude of one hundred years; it would be overwritten by the directional force born from the origin. However, humans (human bodies) who were overwritten by their Origins would acquire great powers.
Araya Souren learned the technique to awaken Origins during his research into the root of humanity.
Of course, he only awakened the Origin of one person.

Magus•Magic circuit
Magic circuits are the pseudo nerves that a magus has inside himself. These are paths that generate magic energy and access the magic foundation engraved in the world. Magi make magic energy with the magic circuits and use the magic energy to run the magic foundation and thus put magery into effect. To do either of these, the magic circuits are necessary.

As suggested by the description pseudo nerves, these are split into cores and lines joining these together and are spread throughout the body.

The number of magic circuits are fixed at birth and the number won't increase by other than external factors.

•Magic crest
The product of stamping the anchored mystery that a magus had spent his entire life building up. Can be said to be mystical inheritance that defines the magus line as a magus line. While the inheritor is young, it is necessary to implant this little at a time while at the same time having the body adjust to the magic crest by medicine and rituals. The magic association also has technology for extracting just the magic crest from the body and storing it.

•Magus alignment
What determines what kind of attributes a magus' magic is going to be likely to have, or what kind of magic the magus is going to have good chemistry with, is going to be the element aligned with the magus.
In addition to the five great elements of earth, water, fire, wind, and sky, there's the imaginary elements of Hollow and Nothing, for a number of seven.
Some of the five elements will differ according to the school of magic. A famous one is a style in which the five great elements are formed from wood, fire, soil, metal,and water.
Basically, one magus has one alignment, but sometimes there are magi with two alignments (like fire and earth, wind and water) and there are also those called "Average Ones" who have all the five great elements.

Matou Sakura normally would have been a holder of the imaginary element of Emptiness. However, through her magic training, hers had been changed to the water alignment of the Matou line, so she couldn't exhibit her true talent.

Normal alignments

Elements

Explanation

Five great elements

Earth

One of the two alignments of Kiritsugu. Kiritsugu exhibited his attribute of combining and used magic which combined the wounds of an enemy in a different form than normal, and made them unhealable.

Five great elements

Water

The alignment that the Matou magi have had for generations. Matou exhibit the attribute of absorption and have passed it on. Sakura's alignment changed from Emptiness to water.

Five great elements

Fire

The alignment of Tokiomi and also one of the two alignments of Kiritsugu. It is the symbol of life and death and has good chemistry with destructive magic.

Five great elements

Wind

One of the two alignments of Kayneth Elmelloi Archibold. There are few magi with wind as an alignment

Five great elements

Sky

An element which makes up celestial bodies that is newly added as a fifth element to the four great elements of earth, water, fire, and wind. This is, in other words, Ether.

Imaginary Elements

Hollow

The alignment that Sakura was born with. Defined, in magery, as that "which is possible but is not in the physical plane". Also called imaginary numbers.

Imaginary Elements

Nothingness

Like Hollow, the alignment of an imaginary element. In magery, defined as that "which is not possible, but materializes". Has a different meaning that the "nothing" of physics and math.

•The absoluteness called Origin
If alignment determines the root of one's magic, then even deeper than that, is the origin which determined the root of one's existence. The origin is not only for magi, but is the orientation that all things are born with and it's existence itself is thought absolutely necessary.
Those magi with an origin that is strongly expressed outwardly are sometimes removed from the normal alignments and there are times that the origin itself becomes the alignment. Most of those magi exhibit their talents as extreme specialists.
Because of that, it's said that they can reach higher grounds than normal magi.

Shirou Emiya's origin is "Sword" and his alignment as a Magus is also "Sword". He is unable to use magic of the five great elements with precision because he doesn't have any of them as an alignment, but it does allow for the manifestation of "Unlimited Blade Works."

•Noble Colors
Of the alignments, wind is called "noble" and fire is "normal". By the way, the term "Noble Colors" is used to refer to special and innate things where he workings of the magic circuit are close to the movements of a celestial body (normally they're closer to the movements of the crust), and is innate and special.
Noble Colors are often used to refer to mystic eyes, and Rider's petrifying mystic eyes are also a noble color.

"I failed 2 years ago. That person was too different. What was needed were those who had diverged from the same 'origin'.
That's right. Be happy, Ryougi Shiki. Those two were sacrifices that I prepared for you."

Rin realizes that the attacks are not from the black shadow, but a magic Sakura possessess. The magic of Matou is to bind others. But Sakura is originally from the Tohsaka family --- a shadow-user with an Origin of the imaginary element, Imaginary Numbers. Matou Sakura is able to embody the black shadow to that degree because she has both attibutes ---!

Q: Archer's greatest defense is "Rho Aias", but if he were the same person as Shirou...

Q: Archer's greatest defense is "Rho Aias", but if he were the same person as Shirou, shouldn't his greatest protection be "Avalon"? In the Rin route, Archer knew that the holy sword's sheath was inside Shirou, so wouldn't the Heroic Spirit form of the Shirou that "knew" that the sheath was merged with him be Archer?

A: Avalon’s power won't work if Saber's not connected to it. It's a different story during the Grail War, but all it does when Saber isn't around is make Shirou's magic attribute into "sword". Also, after the Grail War is taken apart, the line between him and her will be gone, so it's best to think that his image of "Avalon" also disappeared.